1. Technical Field
The present invention relates to a method of assembling a tongue assembly for use in a vehicle seat belt system to help restrain movement of an occupant of a vehicle or of a child seat in a vehicle.
2. Description of the Prior Art
A known vehicle seat belt system is a three-point continuous loop seat belt system. A three-point continuous loop seat belt system includes a seat belt retractor and a length of belt webbing. The belt webbing extends from the retractor through a D-ring fixed to the vehicle and then down to an anchor point near the vehicle floor. A tongue assembly is slidable along the length of belt webbing between the D-ring and the anchor point. To use the seat belt system, a vehicle occupant grasps the tongue assembly and inserts it into a buckle. When the tongue assembly is fastened in the buckle, a portion of the belt webbing extends across the lap of the vehicle occupant and a portion of the belt webbing extends diagonally across the torso of the vehicle occupant. When the tongue assembly is released from the buckle, the belt webbing is wound onto the retractor.
The tongue assembly should slide along the belt when the occupant moves the tongue assembly toward the buckle. The tongue assembly should also slide along the belt after the occupant unlocks the tongue assembly from the buckle so that the retractor can fully wind up the belt. The retractor would otherwise carry the tongue assembly upwardly to the D-ring, whereupon further movement of the belt would be prevented as the D-ring blocked further movement of the tongue assembly. Conversely, when the subject tongue assembly is locked in the buckle, it should cinch the belt webbing, that is, block movement of the belt webbing through the tongue assembly. This cinching action helps to restrain movement of the vehicle occupant in the event of a vehicle collision, and helps to secure a child seat in position on the vehicle seat. This cinch device is designed to cinch the webbing up to a predetermined load. Loads above the predetermined load may cause the webbing to translate but the occupant is still restrained.